Firearms with changeable barrels are desirable because the barrel can be replaced as the barrel becomes damaged or too hot, to change the firearm's caliber, or for more compact storage of the firearm.
Heavy machine guns, particularly those with air cooled barrels, often require barrel changes in the field because the barrel has become too hot for continued use without permanently damaging the barrel. Various quick-change mechanisms using latches or pins have been developed to permit rapid barrel replacement of heavy machine guns.
Although a variety of bolt action and semi-automatic and automatic rifles permit barrel changes, they typically require specialized tools. For example, to change an AR-15 barrel, the upper receiver is held in a vise block to provide a secure and steady hold on the upper receiver, a specialized barrel nut wrench is used to unscrew the barrel nut so the barrel can be removed, and a torque wrench must be attached to the specialized barrel nut wrench in order to tighten the barrel nut once the new barrel is in place. An alternative modular rifle system design eliminates the need for a vise block, but requires attaching a specialized takedown/assembly tool to the receiver and using a gear drive torque wrench to engage gear teeth on a specialized barrel design in order to tighten and loosen the barrel.
The disadvantages of both of these approaches are the need for specialized tools and associated difficulties associated with changing barrels in the field. Not only is there a risk of under torqueing or over torqueing the receiver or barrel nut, resulting in loosening or breakage, but it is also easy to lose the aim of an attached scope. The user may not notice the misalignment of the scope until after taking a shot that misses or strikes an unintended target.
Therefore, a need exists for a new and improved firearm that can be used to change barrels having a standard barrel thread in such a manner that under torqueing or over torqueing are not possible and an attached scope is unlikely to be disturbed. In this regard, the various embodiments of the present invention substantially fulfill at least some of these needs. In this respect, the firearm with barrel cinching clamp according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in doing so provides an apparatus primarily developed for the purpose of facilitating barrel replacement when the barrel becomes damaged or too hot, to change the firearm's caliber, or for more compact storage of the firearm.